Im using reallfow 2015, and yesterday I simulate some softbody dynamics and everything was working fine, but today Realflow start waiting about a minute before start simulating. I tried restarting the machine etc. I was facing the same problem before but then realflow was waiting about 5 sec, and I read somwhere, maybe in this forum about the problem and somehow I was able to fix it. But now I can find the tread or something simmilar.

I don't remember that this would be something that can be changed much. I believe, the program is preparing the simulation framework in this time, for example filling/defining collision volumes and surfaces or distributing tasks for multiple threads. I see this especially with hybrido simulations. What you could try as a fix is limiting the number of threads (processor cores) in the simulation settings.

I do know dense geometry meshes combined with a very low cell size for object collisions can result in a very long "pre-process" that makes the program look like it hangs for a bit. I'm sure there are other scene-dependent things that cause it too.